Which has better water resistance, the Aera Instruments M-1 or the Sheffield 1A 38 dive 38mm, 3-hand date (rotating dive bezel, perforated rubber strap)?

The Sheffield 1A 38 dive 38mm, 3-hand date (rotating dive bezel, perforated rubber strap) is rated to 200m versus 100m for the Aera Instruments M-1.

What movement does the Aera Instruments M-1 run compared to the Sheffield 1A 38 dive 38mm, 3-hand date (rotating dive bezel, perforated rubber strap)?

The Aera Instruments M-1 runs a manual caliber (Sellita SW216-1), while the Sheffield 1A 38 dive 38mm, 3-hand date (rotating dive bezel, perforated rubber strap) runs a automatic (Seiko NH35).

Side by side

Aera Instruments M-1vsSheffield 1A 38 dive 38mm, 3-hand date (rotating dive bezel, perforated rubber strap)

Q: Which is bigger, the Aera Instruments M-1 or the Sheffield 1A 38 dive 38mm, 3-hand date (rotating dive bezel, perforated rubber strap)?

The Aera Instruments M-1 wears larger at 39mm versus 38mm for the Sheffield 1A 38 dive 38mm, 3-hand date (rotating dive bezel, perforated rubber strap) — a 1mm difference across the dial.

The numbers, the dial colors, the calibers — laid out so you can stop flipping between tabs.

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Aera Instruments M-1

Sheffield 1A 38 dive 38mm, 3-hand date (rotating dive bezel, perforated rubber strap)

MSRP $223

Buy from Aera Instruments ↗

Buy used on eBay ↗

Buy from Sheffield ↗

Buy used on eBay ↗

At a glance

11 of 29 specs differ

Diameter

M-139mm

1A 38 dive 38mm, 3-hand date (rotating dive bezel, perforated rubber strap)38mm

Power Reserve

M-142h

1A 38 dive 38mm, 3-hand date (rotating dive bezel, perforated rubber strap)—

Water Resistance

M-1100m

1A 38 dive 38mm, 3-hand date (rotating dive bezel, perforated rubber strap)200m

MSRP

M-1—

1A 38 dive 38mm, 3-hand date (rotating dive bezel, perforated rubber strap)$223

Full specifications

Case

5 specs

Crystal & Dial

2 specs

Dial Color

Dune

Blue

Lume

Super-LumiNova

None

Movement

3 specs

Caliber

Sellita SW216-1

Seiko NH35

Type

Manual

Automatic

Power Reserve

42h

—

Pricing

1 specs

MSRP

—

$223

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Aera Instruments M-1vsSheffield 1A 38 dive 38mm, 3-hand date (rotating dive bezel, perforated rubber strap)

At a glance

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